SUMMARY: The optimum conditions for storing viable articular cartilage as measured by safranin O staining, hexosamine, hydroxyproline, DNA, and protein content, 35SO4 and 14C-proline uptake and release, and flow-independent viscoelastic shear modulus and flow-dependent indentation testing will be determined by modifying the storage conditions. Rabbit articular cartilage slice explants and whole condyles will be stored for 10 and 30 days in M.E.M. Eagle/NCTC 135/15% fetal calf serum at 37 degrees C. in 5% CO2 and air with various concentrations and combinations of ascorbic acid alpha-tocopherol, hyaluronate, protease inhibitors, and periodic mechanical compression. The biosynthesis and degradation of collagen and proteoglycan of stored articular cartilage will be determined, as well as the changes in collagen type, and the changes in glycosaminoglycan composition of proteoglycans, synthesized during cartilage storage. Quantitative zonal analysis of chondrocyte cytoplasmic components of freshly excised vs stored rabbit articular cartilage will be determined by point-counting analysis of electron micrographs. The histological, biochemical, and mechanical properties of stored, transplanted rabbit articular cartilage shell allografts will be determined, as well as the cellular and numeral immune responses induced by fresh and stored articular cartilage allografts.